In the last two decades, the theory of variational analysis including variational inequalities (VI) emerged as a rapidly growing area of research because of its applications in nonlinear analysis, optimization, economics, game theory, and so forth. In the recent past, many authors devoted their attention to study the VI defined on the set of fixed points of a mapping, called hierarchical variational inequalities. Very recently, several iterative methods have been investigated to solve VI, hierarchical variational inequalities, and triple hierarchical variational inequalities. In the recent past, Ekeland's type variational principle has been studied in the setting of nonconvex metric spaces. It also has been generalized for bifunctions and set-valued mappings.

This special issue aims to promote the exchange of ideas between researchers and to spread new trends in these areas. It will focus on all aspects of variational analysis, variational inequalities, optimization, fixed point theory, and their applications in different areas of science, engineering, and social sciences. Potential topics include, but are not limited to:

• Variational analysis
• Optimization
• Variational inequalities
• Hierarchical variational inequalities
• Ekeland's variational principle
• Fixed point theory
• Iterative methods for variational inequalities and fixed point problems
• Applications of variational inequalities to optimization theory